Osmocom Multiplex Protocol

Files
file	osmux.h
file	osmux.c
	Osmocom multiplex protocol helpers.

Data Structures
struct	osmux_hdr
struct	osmux_in_handle
struct	osmux_out_handle
struct	osmux_batch
struct	osmux_circuit
struct	osmux_input_state
struct	osmux_tx_handle

Macros
#define	OSMUX_FT_SIGNAL   0
#define	OSMUX_FT_VOICE_AMR   1
#define	OSMUX_FT_DUMMY   2
#define	OSMUX_MAX_CONCURRENT_CALLS   8
#define	OSMUX_BATCH_DEFAULT_MAX   1472
#define	DELTA_RTP_MSG   20000
#define	DELTA_RTP_TIMESTAMP   160
#define	SNPRINTF_BUFFER_SIZE(ret, size, len, offset)

Functions
struct osmux_hdr	__attribute__ ((packed))
static uint8_t *	osmux_get_payload (struct osmux_hdr *osmuxh)
int	osmux_snprintf (char *buf, size_t size, struct msgb *msg)
void	osmux_xfrm_input_init (struct osmux_in_handle *h)
void	osmux_xfrm_input_fini (struct osmux_in_handle *h)
int	osmux_xfrm_input_open_circuit (struct osmux_in_handle *h, int ccid, int dummy)
void	osmux_xfrm_input_close_circuit (struct osmux_in_handle *h, int ccid)
int	osmux_xfrm_input (struct osmux_in_handle *h, struct msgb *msg, int ccid)
void	osmux_xfrm_input_deliver (struct osmux_in_handle *h)
void	osmux_xfrm_output_init (struct osmux_out_handle *h, uint32_t rtp_ssrc)
int	osmux_xfrm_output (struct osmux_hdr *osmuxh, struct osmux_out_handle *h, struct llist_head *list)
struct osmux_hdr *	osmux_xfrm_output_pull (struct msgb *msg)
void	osmux_tx_sched (struct llist_head *list, void(*tx_cb)(struct msgb *msg, void *data), void *data)
static uint32_t	osmux_get_payload_len (struct osmux_hdr *osmuxh)
static uint32_t	osmux_ft_dummy_size (uint8_t amr_ft, uint8_t batch_factor)
static struct msgb *	osmux_rebuild_rtp (struct osmux_out_handle *h, struct osmux_hdr *osmuxh, void *payload, int payload_len, bool first_pkt)
static int	osmux_batch_enqueue (struct msgb *msg, struct osmux_circuit *circuit, uint8_t batch_factor)
static void	osmux_batch_dequeue (struct msgb *msg, struct osmux_circuit *circuit)
static void	osmux_circuit_del_msgs (struct osmux_batch *batch, struct osmux_circuit *circuit)
static int	osmux_batch_put (struct osmux_batch *batch, struct osmux_input_state *state)
static int	osmux_xfrm_encode_amr (struct osmux_batch *batch, struct osmux_input_state *state)
static void	osmux_encode_dummy (struct osmux_batch *batch, uint8_t batch_factor, struct osmux_input_state *state)
static struct msgb *	osmux_build_batch (struct osmux_batch *batch, uint32_t batch_size, uint8_t batch_factor)
static void	osmux_batch_timer_expired (void *data)
static int	osmux_rtp_amr_payload_len (struct msgb *msg, struct rtp_hdr *rtph)
static void	osmux_replay_lost_packets (struct osmux_circuit *circuit, struct rtp_hdr *cur_rtph, int batch_factor)
static struct osmux_circuit *	osmux_batch_find_circuit (struct osmux_batch *batch, int ccid)
static struct osmux_circuit *	osmux_batch_add_circuit (struct osmux_batch *batch, int ccid, int dummy, uint8_t batch_factor)
static void	osmux_batch_del_circuit (struct osmux_batch *batch, struct osmux_circuit *circuit)
static int	osmux_batch_add (struct osmux_batch *batch, uint32_t batch_factor, struct msgb *msg, struct rtp_hdr *rtph, int ccid)
static void	osmux_tx_cb (void *data)
static void	osmux_tx (struct msgb *msg, struct timeval *when, void(*tx_cb)(struct msgb *msg, void *data), void *data)
static int	osmux_snprintf_header (char *buf, size_t size, struct osmux_hdr *osmuxh)
static int	osmux_snprintf_payload (char *buf, size_t size, const uint8_t *payload, int payload_len)

Variables
struct osmux_in_handle	__attribute__
static void *	osmux_ctx

Detailed Description

Macro Definition Documentation

#define SNPRINTF_BUFFER_SIZE	(		ret,
			size,
			len,
			offset
	)

Value:

size += ret;                                    \
        if (ret > len)                                  \
                ret = len;                              \
        offset += ret;                                  \
        len -= ret;

Function Documentation

int osmux_xfrm_input	(	struct osmux_in_handle *	h,
		struct msgb *	msg,
		int	ccid
	)

osmux_xfrm_input - add RTP message to OSmux batch

Parameters

msg	RTP message that you want to batch into one OSmux message

If 0 is returned, this indicates that the message has been batched or that an error occured and we have skipped the message. If 1 is returned, you have to invoke osmux_xfrm_input_deliver and try again.

The function takes care of releasing the messages in case of error and when building the batch.